All marine areas and habitats are currently affected by human disturbances and a large fraction is strongly affected by multiple stressors. Especially shallow coastal benthic systems, which represent some of our most valued ecosystems, increasingly experience anthropogenic stressors and disturbances along with the expanding human population. A particular stressor for many shallow coastal habitats is the change in sediment transport processes that alter benthic and pelagic sediment properties. Such changes can for example result from dredging or urban development in the catchment area that may enhance sediment input in the marine ecosystem.
There is growing evidence that interactions between intrinsic ecological dynamics and stressor effects can also lead to the loss of resilience and thus an increased risk of regime shifts to occur. These critical shifts are currently impossible to predict, but the implications are clear: homogenization of communities and ecosystems owing to reductions in foodweb complexity, diversity within functional groups, and biogenic habitat structure, as well as decreases in the size of organisms. In order to predict when an environmental (e.g. sediment load) or biological driver (e.g. change in behavior of an ecosystem engineering species) is sufficiently strong to force an ecological system into an alternative stable state, it is necessary to gain insights into the ecological mechanisms that underpin resilience of the ecosystem.
In this thesis, experiments will be designed and performed that will enhance the understanding of benthic and pelagic sediment change effects on marine benthic biodiversity and ecosystem functioning. You will work with benthic invertebrates that affect functioning of soft-sediment ecosystems, through e.g. feeding and ecosystem engineering interactions.